I have one of these.
https://www.ebay.com/itm/Slip-Ring-...347560?hash=item468273f2a8:g:32AAAOSwzXtbPgcW

Note that the listing say 300 RPM max, that is only 5 revolutions per second. I think that might be too slow for persistance of vision to create a whole picutre.

 

Note that the listing say 300 RPM max, that is only 5 revolutions per second. I think that might be too slow for persistance of vision to create a whole picutre.

Good point ... maybe he could experiment with a hand held drill to which a piece of tape is attached, and see at what minimum RPMs the effect works best?

 

Note that the listing say 300 RPM max, that is only 5 revolutions per second. I think that might be too slow for persistance of vision to create a whole picutre.

Yep saw that but I am betting it can be pushed well beyond that. It might not last for years but who cares.

My limiting factor of concern is transmitting of the data via the slip ring.

I will probably be putting the pic on the spinning board. I was going to add bluetooth anyway. I properly designed program will let me play with the various timing parameters and could also provide useful feedback (RPM speed etc). Debugging will be a challenge getting the Pickit# connected to a spinning board.

 

Good point ... maybe he could experiment with a hand held drill to which a piece of tape is attached, and see at what minimum RPMs the effect works best?

I already have a motor all set up waiting to be tested but the drill is a great idea. The experiment will be two fold.

1. Test if slip ring holds up to higher RPM

2. Test if I reliably transmit to my shift register via a slip ring. I already have the shift register bread boarded and working. Just need to add the slip ring into the mix.

 

My new digital tach just came in so I will be able to easily check the RPM!

 

My new digital tach just came in so I will be able to easily check the RPM!

View attachment 162266

And it's not just a tach ... the thing is intelligent! ...

 

And it's not just a tach ... the thing is intelligent! ...

Yeah look at that. I pressed the create propeller clock button and it spit out all of the circuit design and code.

 

Yeah look at that. I pressed the create propeller clock button and it spit out all of the circuit design and code.

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LOL the motor I selected does not even have enough torque to overcome the resitance of the slip ring. Funny it does not feel all that tight when I spin it by hand.


I tried the drill idea. Holds up just fine to 2000 RPM. Well over the 300 RPM limit as I expected.

 

Anyone want to buy a slip ring?

 

Anyone want to buy a slip ring?

Why not buy a larger motor? Or use the motor of a cheap-o air fan?

 

Why not buy a larger motor? Or use the motor of a cheap-o air fan?

The problem with a fan would be getting an axle mounted dead center. Then how to mount it? I suppose it could be glued?

I have a much larger motor that would be over kill but no coupler for it.

But I still don't know if I can successfully reliably transmit serial data via the slip ring. I guess I could test that with the drill pretty easily.